California rivers are so swollen from runoff that the impact is easily seen in these before and after satellite images

By Tom Yulsman | February 11, 2017 6:08 pm

An animation of satellite images taken about a year apart shows a huge difference in the amount of water flowing through waterways in California’s Sacramento River Delta. (Images: NASA Worldview. Animation: Tom Yulsman)


This animation of satellite images shows in dramatic fashion just how far California has come following one of its most devastating droughts on record.

To get the full effect, make sure to click on the animated GIF.

On Feb. 9, 2016, California was still in the grips of the drought. At that time, the waterways of the Sacramento River Delta were barely visible from space, as seen in the first image of the animation, acquired by NASA’s Aqua satellite. The second image, acquired today by Terra, Aqua’s twin, shows those waterways swollen and laden with brown sediment.

Also take a look at the coastal waters. The animation reveals that a lot more sediment is flowing into the ocean than a year ago — because so much more runoff is flowing out to sea.

| Story updated 2/13/17 with this new animation:


A closer before-and-after satellite view of the Sacramento River Delta area. One image was acquired by the Aqua satellite on Feb. 8, 2016; the other on Sunday, Feb. 12, 2017 by Terra, Aqua’s twin. The Sacramento River Delta is downstream of Lake Oroville, the massive reservoir to the north where severe erosion of the emergency spillway prompted evacuation of 188,000 people on February 12th. (Images: NASA Worldview. Animation: Tom Yulsman) |

In fact, there’s so much runoff from the huge amount of precipitation California has received in recent weeks that the Sacramento Bee is reporting this

After five years of drought, could California really have so much rain and snow there’s no room to store all the water?

The answer – as the state’s water picture careens from bust to boom – is yes.

The Oroville Dam north of Sacramento actually overflowed today, with water topping the emergency spillway. The California Department of Water Resources emphasizes that there is no risk to the dam, or of flooding downstream along the Feather River at this time, and there is no imminent threat to the public.

Nonetheless, this is pretty dramatic:

This is drone video, shot just this morning, of water pouring over the dam’s auxiliary spillway. The reservoir is at 149 percent of the historical average for Feb. 11.

Water pouring into the Feather River from Lake Oroville is making its way south into the Sacramento River Delta and adding to the flows there that have become visible from space.

UPDATES: Since I first wrote this post, Lake Oroville’s emergency spillway eroded severely, threatening massive flooding downstream. I’ll be posting updates on the situation here.

Feb. 13, 9 a.m. MST: Since ordering evacuation of about 188,000 people downstream, Lake Oroville’s level dropped enough to stop the flow over the emergency spillway. Crews have been filling large, 1-ton bags of rocks and plan to drop them by helicopter into the spillway to temporarily repair the damage. Meanwhile, California’s Department of Water Resources is hoping to drop the lake level by 50 feet over the next few days in an effort to make room for new water expected to pour into the reservoir from a storm forecast for later in the week. 

Here’s a great aerial view of water pouring over the emergency spillway before it stopped last night: 

Also, this failure of the spillway to work as intended should not have been a complete surprise. The San Jose Mercury News is reporting that 12 years ago, federal and state officials ignored warnings that this could happen. 

Feb. 12: Less than a day after the DWR said there was no risk to the emergency spillway and everything was under control, everything has, in fact, changed. Today, Sunday, the earthen spillway suffered extreme erosion and became at risk of total failure. This prompted the evacuation of 130,000 people downstream to protect them from the potential for catastrophic flooding. As I am writing this at 10:30 p.m. California time, the situation is unclear. But there is a glimmer of good news: On Twitter, the Sacramento Bee is reporting that the DWR says water is no longer flowing over the spillway. By morning, we’ll know more. I’ll check in then and provide an update. 


  • kapnlogos

    The big problem now is how to keep all the extra regulations and fees in place that were meant to deal with the drought. Even as the dams and streams were overflowing the bureaucrats wouldn’t admit the drought was over.

    • Kurt S

      Im sorry, but I think you have failed to understand the hydrology of the area. The rivers will quickly (hydrologically speaking) rid the excess water. Then in summer those rivers rely on the amount of snow pack (mostly), and glacier melt. Most of the precipitation fell as rain instead of snow, therefore the snow pack is not sufficient enough to end this coming summers drought. So there wassome relief from drought, and thankfully many reservoirs have been replenished. But in the end, there is still a water deficit, hence drought.
      And just in case you dont understand what water deficit means….it means more water is used than what is available in the snow pack, reservoirs, rivers, etc..

      • kapnlogos

        It depends on what you define as a drought. You can define ‘water deficit’ as a drought, but who defines that? If a drought is the condition of using more water than is available then the definition can be very subjective. You don’t understand the point of my comment was the reluctance of the bureaucracies to announce a drought was over, even as the dams were filled to overflowing and rivers brimming with water. Government always uses problems to increase it’s control, and is never going to put itself out of a job.

        • okiejoe

          One extremely wet year does not necessarily end a drought, next year could see a return to drought conditions. One can declare an “end” to a drought only in retrospective.

          • kapnlogos

            So no matter how much it rains, or how much water they release from the dams, we won’t know if ‘the drought’ is over? We can safely assume that the government won’t be doing that any time soon, but in the meantime keep your car full of gas and be ready to head for the hills.

          • OWilson

            It’s not a drought unless the government says it is!

            It’s not over until the government says it is!

            The problem with that true believer premise, is that it depends on WHICH government!


          • OWilson

            But with catastrophic global warming we can see it a hundred years in advance?

            Ah, I see! :)

        • OWilson

          The government’s “Severe Drought” areas cover places like Death Valley, and the natural deserts of South West U.S.

          That’s all you need to know about the government fake news scaremongering!

          • kapnlogos

            Death Valley’s iconic Scotty’s Castle was closed a few years ago (2015) due to flooding, which washed out the roads and flooded the structure. The park was to be closed for a year. The wildflowers sure bloomed nicely that year.

          • Mike Richardson

            Again with the “Fake news?”

          • OWilson

            Fake news is for for true believers.

            Hillary ahead by 14.

            Trump has no path to 270 Electoral votes :)

          • Mike Richardson

            Since you just couldn’t resist going political, I guess in lieu of “Fake News,” I can provide “alt news” for the eager consumption of the alt.right. Quite ironic (as always), when one considers the pathological lies promoted and embraced by this group. For example, how we should be frightened of the massacre at Bowling Green, Kentucky. Or the tragic terrorist attack in Sweden this weekend. Or Trump’s enormous electoral victory, the biggest by far (and that’s not counting his decisive popular vote victory, when you throw out all the illegal aliens who voted). More topical to this discussion, the accusation that Global Warming is a hoax perpetrated by the Chinese, and/or by Marxists determined to bring down all capitalist societies.

            Well, at least you’re fortunate enough to live in a country led by a man whose last name starts with “Tru,” but actually prefers truth to alternative reality. Then again, your apparent fondness for Trump might just be because he shares that willingness to reject any facts that get in the way of what he chooses to believe. True believers indeed. 😀

          • OWilson

            More lies from “fake news” Mikey.

            Trump actually said, “”We’ve got to keep our country safe. You look at what’s happening in Germany, you look at what’s happening last night in Sweden,”

            He never mentioned “terrorism” or a “terror attack”

            You and your demented fake news MSM made that up out of thin air!

            He was talking about the recent crime wave and the unrest, like :

            Newsflash! Feb 20, 2017

            “Riots broke out in a predominantly immigrant neighborhood in the northern suburbs of the country’s capital, Stockholm.

            “The neighborhood, Rinkeby, was the scene of riots in 2010 and 2013, too. And in most ways, what happened Monday night was reminiscent of those earlier bouts of anger. Swedish police apparently made an arrest on drug charges at about 8 p.m. near the Rinkeby station. For reasons not yet disclosed by the police, word of the arrest prompted youths to gather.

            “Over four hours, the crowd burned about half a dozen cars, vandalized several shopfronts and threw rocks at police. Police spokesman Lars Bystrom confirmed to Sweden’s Dagens Nyheter newspaper that an officer fired shots at a rioter but missed. A photographer for the newspaper was attacked and beaten by more than a dozen men and his camera was stolen”

            But as Mikey says, “It’s “only property”.


          • Mike Richardson

            So he was predicting the future, the?! Wow! February 20th was yesterday, btw. Epic fail. LOL!

          • OWilson

            2010 and 2012, also!


            Last word to you!

          • Mike Richardson

            Awww, so sorry to see you go! Buh-bye.

            Now, for anyone else wanting to see why Ol’ Wilson continues to fail on these posts (other than ironically accusing others of lying), let’s take a look at Trump’s Sweden comment in proper context:
            “We’ve got to keep our country safe. You look at what’s happening in Germany. You look at what’s happening last night in Sweden. Sweden, who would believe this? Sweden. They took in large numbers. They’re having problems like they never thought possible. You look at what’s happening in Brussels. You look at what’s happening all over the world. Take a look at Nice. Take a look at Paris.”
            Paris, Brussels, Nice — all referenced terrorist attacks. The reference then to Sweden, as “what’s happening last night,” could only logically be construed as such, given the context. But the chronology was wrong, as clearly no terrorist attack had occurred the previous day. Now one month prior, there had been an arrest in a foiled terror attack in Gothenburg — three suspected neo-Nazis planted a homemade bomb in a refugee center in the Swedish city. But I’m sure that’s not what Trump was talking about.

            You see, context matters. Chronology matters. Facts matter. In this blog post, for example, the author reported the facts, and noted the context and chronology of the events within California’s history of drought even prior to climate change. This, like the reporting on the inaccuracies and outright lies of the Trump administration and its surrogates, is not fake news — it’s fact based. Something folks with Trump’s Unbelievable Reality Denying Syndrome may not be able to comprehend, but important for those interested in truth and integrity in reporting.

          • OWilson

            What a load of left wing crud!

            You need to get a real life! :)

          • Mike Richardson

            Not surprisingly, no actual facts to counter anything I said, nor anything to support your assertion that I was lying, while you engaged in bending or breaking the truth yourself (gotta love your lack of irony recognition there). Also, inability to comprehend the concept of “Last word to you!.” LOL!

  • OWilson

    Thanks for the report!

    So in a single year we have gone from “the new normal” record drought to plentiful rain and snow! The troubling newspaper headline photos of dry river beds have, almost instantly, been replaced with photos of flooding.

    I love the way Mother Nature deals with hype!

    But, after all, she has been in this business a long time!

    Reminding us that the climate is humanity’s friend, not “The Greatest Threat Humanity Faces”

  • Tom Yulsman

    Mr. Wilson and kapnlogos: Keep your shirts on. The paleo record shows that large western U.S. droughts can be punctuated from time to time by periods of robust precipitation. We could experiencing something like that in the next couple of years. Or not. Time will tell.

    One thing is certain: We talk about the hydrologic cycle in the West incorrectly. John Wesley Powell was absolutely correct: We should think of drought in this region as the norm, with wet times being unusual. (And Mr. Wilson: Please note that I am saying nothing here about human-caused climate change. I am simply talking about what natural variation is capable of doing all by its lonesome.)

    • OWilson

      Of course.

      The absence of any reference to AGW in an article on California weather is noted!

      (But noteworthy!) :)

  • CarolAST

    “The California Department of Water Resources emphasizes that there is no risk to the dam, or of flooding downstream along the Feather River at this time, and there is no imminent threat to the public.”

    Ooops. “Thousands from Yuba, Butte, Sutter counties evacuated”

    • OWilson

      Only around 6% of folks have a high degree of confidence in the government, or the Media. (Gallup)

      The good news is, with the numbers at that level, things have to change.

      Sometimes dramatically!

  • John C

    they need more rational water management out there
    you live in a desert punctuated by flooding, plan accordingly



ImaGeo is a visual blog focusing on the intersection of imagery, imagination and Earth. It focuses on spectacular visuals related to the science of our planet, with an emphasis (although not an exclusive one) on the unfolding Anthropocene Epoch.

About Tom Yulsman

Tom Yulsman is Director of the Center for Environmental Journalism and a Professor of Journalism at the University of Colorado, Boulder. He also continues to work as a science and environmental journalist with more than 30 years of experience producing content for major publications. His work has appeared in the New York Times, Washington Post, Audubon, Climate Central, Columbia Journalism Review, Discover, Nieman Reports, and many other publications. He has held a variety of editorial positions over the years, including a stint as editor-in-chief of Earth magazine. Yulsman has written one book: Origins: the Quest for Our Cosmic Roots, published by the Institute of Physics in 2003.


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